Update the table of RAM vs number of renderers...

chrome/browser/renderer_host/render_process_host.cc

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/renderer_host/render_process_host.h"
 
 #include "base/rand_util.h"
 #include "base/sys_info.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/notification_service.h"
 
 namespace {
 
 unsigned int GetMaxRendererProcessCount() {
   // Defines the maximum number of renderer processes according to the
   // amount of installed memory as reported by the OS. The table
   // values are calculated by assuming that you want the renderers to
   // use half of the installed ram and assuming that each tab uses
-  // ~25MB.
+  // ~40MB, however the curve is not linear but piecewise linear with
+  // interleaved slopes of 3 and 2.
+  // If you modify this table you need to adjust browser\browser_uitest.cc
+  // to match the expected number of processes.
+
   static const int kMaxRenderersByRamTier[] = {
-    4,                                  // less than 256MB
-    8,                                  // 256MB
-    12,                                 // 512MB
-    16,                                 // 768MB
+    3,                        // less than 256MB
+    6,                        //  256MB
+    9,                        //  512MB
+    12,                       //  768MB
+    14,                       // 1024MB
+    18,                       // 1280MB
+    20,                       // 1536MB
+    22,                       // 1792MB
+    24,                       // 2048MB
+    26,                       // 2304MB
+    29,                       // 2560MB
+    32,                       // 2816MB
+    35,                       // 3072MB
+    38,                       // 3328MB
+    40                        // 3584MB

[darin (slow to review), 2009/02/19 18:40:02]

40 seems too high to me.  can we just double our previous limits for a start?

   };
 
   static unsigned int max_count = 0;
   if (!max_count) {
     size_t memory_tier = base::SysInfo::AmountOfPhysicalMemoryMB() / 256;
     if (memory_tier >= arraysize(kMaxRenderersByRamTier))
       max_count = chrome::kMaxRendererProcessCount;
     else
       max_count = kMaxRenderersByRamTier[memory_tier];
   }
@@ skipping 116 matching lines @@
 
   return NULL;
 }
 
 void RenderProcessHost::Unregister() {
   if (host_id_ >= 0) {
     all_hosts.Remove(host_id_);
     host_id_ = -1;
   }
 }